38206 2010-04-27 11:00:29 -0700 FrameView::paintContents() incorrectly bails if needsLayout() is true sometimes 2010-10-06 05:24:12 -0700 1 1 1 Unclassified WebKit Layout and Rendering 528+ (Nightly build) All OS X 10.5 RESOLVED DUPLICATE 32381 P2 Normal --- 1 simon.fraser simon.fraser mitz simon.fraser zimmermann oldest_to_newest 217792 0 simon.fraser 2010-04-27 11:00:29 -0700 FrameView::paintContents() asserts, and then bails if FrameView::needsLayout() is true, with the assumption that said layout will happen soon, and do whatever repainting it needs to. It also assumes that the -viewWillDraw machinery will ensure that layout has always happened before painting. Note that FrameView's needsLayout() is more inclusive than root->needsLayout(); it also checks for childNeedsStyleRecalc() and needsReapplyStyles(). http://trac.webkit.org/changeset/57919 introduced a change that causes setNeedsStyleRecalc() on a node in the middle of a -viewWillDraw call, which happens on a stack that looks like this: #0 WebCore::RenderView::compositingStateChanged (this=0x122bfb5a8) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderView.cpp:718 #1 0x0000000102d787cf in WebCore::RenderLayerCompositor::enableCompositingMode (this=0x122bfb730, enable=true) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderLayerCompositor.cpp:121 #2 0x0000000102d78809 in WebCore::RenderLayerCompositor::updateBacking (this=0x122bfb730, layer=0x106d1d1f8, shouldRepaint=WebCore::RenderLayerCompositor::CompositingChangeRepaintNow) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderLayerCompositor.cpp:257 #3 0x0000000102d789fd in WebCore::RenderLayerCompositor::updateLayerCompositingState (this=0x122bfb730, layer=0x106d1d1f8, shouldRepaint=WebCore::RenderLayerCompositor::CompositingChangeRepaintNow) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderLayerCompositor.cpp:310 #4 0x0000000102d67ff6 in WebCore::RenderLayer::styleChanged (this=0x106d1d1f8, diff=WebCore::StyleDifferenceEqual) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderLayer.cpp:3472 #5 0x0000000102d35214 in WebCore::RenderBoxModelObject::styleDidChange (this=0x10997ce18, diff=WebCore::StyleDifferenceEqual, oldStyle=0x1241e7bb0) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderBoxModelObject.cpp:297 #6 0x0000000102d2d002 in WebCore::RenderBox::styleDidChange (this=0x10997ce18, diff=WebCore::StyleDifferenceEqual, oldStyle=0x1241e7bb0) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderBox.cpp:165 #7 0x0000000102d9ec11 in WebCore::RenderReplaced::styleDidChange (this=0x10997ce18, diff=WebCore::StyleDifferenceEqual, oldStyle=0x1241e7bb0) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderReplaced.cpp:60 #8 0x0000000102e0239f in WebCore::RenderWidget::styleDidChange (this=0x10997ce18, diff=WebCore::StyleDifferenceEqual, oldStyle=0x1241e7bb0) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderWidget.cpp:209 #9 0x0000000102d94d78 in WebCore::RenderObject::setStyle (this=0x10997ce18, style=@0x7fff5fbfbc60) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderObject.cpp:1536 #10 0x0000000102d9294a in WebCore::RenderObject::setAnimatableStyle (this=0x10997ce18, style=@0x7fff5fbfbca0) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/rendering/RenderObject.cpp:1470 #11 0x0000000102c7bd33 in WebCore::Node::setRenderStyle (this=0x1241920a0, s=@0x7fff5fbfbd00) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Node.cpp:1430 #12 0x00000001027c44ed in WebCore::Element::recalcStyle (this=0x1241920a0, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Element.cpp:956 #13 0x00000001028ee964 in WebCore::HTMLObjectElement::recalcStyle (this=0x1241920a0, ch=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/html/HTMLObjectElement.cpp:219 #14 0x00000001027c474d in WebCore::Element::recalcStyle (this=0x1099925c0, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Element.cpp:979 #15 0x00000001027c474d in WebCore::Element::recalcStyle (this=0x109984050, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Element.cpp:979 #16 0x00000001027c474d in WebCore::Element::recalcStyle (this=0x1099924f0, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Element.cpp:979 #17 0x00000001027c474d in WebCore::Element::recalcStyle (this=0x1099927f0, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Element.cpp:979 #18 0x00000001027c474d in WebCore::Element::recalcStyle (this=0x1225f8490, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Element.cpp:979 #19 0x00000001027c474d in WebCore::Element::recalcStyle (this=0x122ba42b0, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Element.cpp:979 #20 0x00000001027c474d in WebCore::Element::recalcStyle (this=0x12232e050, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Element.cpp:979 #21 0x00000001026cd6c5 in WebCore::Document::recalcStyle (this=0x11c9a8a00, change=WebCore::Node::NoChange) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/dom/Document.cpp:1373 #22 0x000000010283a72a in WebCore::FrameView::layout (this=0x123f80620, allowSubtree=true) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/page/FrameView.cpp:606 #23 0x000000010283b22b in WebCore::FrameView::forceLayout (this=0x123f80620, allowSubtree=true) at /Volumes/InternalData/Development/webkit/OpenSource/WebCore/page/FrameView.cpp:1906 #24 0x0000000101fe4e32 in -[WebHTMLView layoutToMinimumPageWidth:maximumPageWidth:adjustingViewSize:] (self=0x123f801b0, _cmd=0x7fff84a2e761, minPageWidth=0, maxPageWidth=0, adjustViewSize=0 '\0') at /Volumes/InternalData/Development/webkit/OpenSource/WebKit/mac/WebView/WebHTMLView.mm:3097 #25 0x0000000101fd728c in -[WebHTMLView layout] (self=0x123f801b0, _cmd=0x7fff865f362b) at /Volumes/InternalData/Development/webkit/OpenSource/WebKit/mac/WebView/WebHTMLView.mm:3111 #26 0x0000000101fdbe9c in -[WebHTMLView(WebInternal) _layoutIfNeeded] (self=0x123f801b0, _cmd=0x7fff84a2c6db) at /Volumes/InternalData/Development/webkit/OpenSource/WebKit/mac/WebView/WebHTMLView.mm:5452 #27 0x0000000101fd4706 in -[WebHTMLView(WebInternal) _web_layoutIfNeededRecursive] (self=0x1241dc050, _cmd=0x7fff84a2c6be) at /Volumes/InternalData/Development/webkit/OpenSource/WebKit/mac/WebView/WebHTMLView.mm:5469 #28 0x0000000101fdb8ad in -[WebHTMLView(WebPrivate) viewWillDraw] (self=0x1241dc050, _cmd=0x7fff865ff778) at /Volumes/InternalData/Development/webkit/OpenSource/WebKit/mac/WebView/WebHTMLView.mm:1268 #29 0x00007fff85f6a172 in -[NSView viewWillDraw] () #30 0x00007fff85f6a172 in -[NSView viewWillDraw] () This causes needsLayout() to return true, and thus paintContents() to bail. However, there's no guarantee that the subsequent recalcStyle() will result in any layout or repaints, so we end up unpainted. In debug builds, we end up with a red background. 286527 1 simon.fraser 2010-09-28 14:21:48 -0700 http://trac.webkit.org/changeset/58320 removed RenderView::compositingStateChanged(). This bug may no longer be applicable. 290223 2 zimmermann 2010-10-06 05:24:12 -0700 *** This bug has been marked as a duplicate of bug 32381 ***